CVE-2025-4435 Affecting python39:3.9/python39-idna package, versions <0:2.10-4.module_el8.10.0+3849+a48d89aa


Severity

Recommended
high

Based on AlmaLinux security rating.

Threat Intelligence

EPSS
0.59% (47th percentile)

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  • Snyk IDSNYK-ALMALINUX8-PYTHON39-14551561
  • published23 Dec 2025
  • disclosed2 Jul 2025

Introduced: 2 Jul 2025

CVE-2025-4435  (opens in a new tab)

How to fix?

Upgrade AlmaLinux:8 python39:3.9/python39-idna to version 0:2.10-4.module_el8.10.0+3849+a48d89aa or higher.
This issue was patched in ALSA-2025:23530.

NVD Description

Note: Versions mentioned in the description apply only to the upstream python39:3.9/python39-idna package and not the python39:3.9/python39-idna package as distributed by AlmaLinux. See How to fix? for AlmaLinux:8 relevant fixed versions and status.

When using a TarFile.errorlevel = 0 and extracting with a filter the documented behavior is that any filtered members would be skipped and not extracted. However the actual behavior of TarFile.errorlevel = 0 in affected versions is that the member would still be extracted and not skipped.

References

CVSS Base Scores

version 3.1